Fluorescent lamp switch



Nov. 15, 1949 G. B. HORN ETAL 2,487,970

FLUORESCENT LAMP-SWITCH Filed Aug. 18, 1947 2 Sheets-Sheet l Nov. l5, 1949 G. B. HORN ETAL FLUORESCENT LAMP-SWITCH 2 Sheets-Sheet 2 Filed Aug. 18, 1947 Samb..-

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Patented Nov. 15, 1949 UNITED STATES PATENT OFFICE FLUonEscEN'r LAMP swrrcu George B. Horn, Fairfield, and Howard E. Youngs, Norwalk, Conn., assignors to The Wheeler Insulated Wire Company, Inc., Bridgeport, Conn., a corporation of Delaware Application August 18, 1947, Serial No. '169,220

11 Claims. (Cl. V2(l0-5) The present invention relates in general to lighting systems and more especially to an improved switch-unit for lighting systems employing fluorescent lamps.

An object of the invention is to provide a switch-unit of superior construction and utility.

A still further object of the invention is to provide a superior two-button switch-unit which is economical to manufacture and assemble, and which provides a positive on and off snapaction.

A still further object of the invention is `to provide a two-button snap-action switch-unit for iiuorescent lamps wherein relatively simple but positive means is provided for starting the lamp, and wherein the installation of the switch-unit in a lighting circuit is simplied.

With the above and other objects in view, as will appear to those skilled in the art from the present disclosure, this invention includes all features in the said disclosure which are novel over the prior art.

In the accompanying drawings, in which certain modes of carrying out the present invention are shown for illustrative purposes:

Fig. 1 is a` schematic side elevation of the switch-unit of this invention connected in the lighting circuit of a iiuorescent lamp;

Fig. 2 is a vertical longitudinal section partly in side elevation of the switch-unit of this invention, the o position of the push buttons being shown by full lines and the on position by broken lines;

Fig. 3 is a horizontal sectional View on line 3-3 of Fig. 2; I

Fig. 4 is an end elevation in section on line 4- 4 of Fig. 2; f

Fig. 5 is an end elevation in section on line 5-5 of Fig. 2; j

Fig. 6 is an end elevation in section on line 6--6 of Fig. 2;

Fig. 'I is a perspective view of the switch-cover,

looking mainly at the underside thereof;

Fig. 8 is a perspective view of the base of the switch;

Fig. 9 is a perspective view of the rocker-member of the switch-means of the switch;

Fig. 10 is a perspective view of one of the push buttons of the'switch-unit;

Fig. 1l is a perspective View of one of the springs of the rocker-member; and

Fig. l2 is a perspective View of one of the starting-contacts.

It may be explained brieily that certain types of iluorescent lamps comprise sealed gas-lled 66 glass tubes provided at their opposite ends with laments which are connected across a pair of electrodes, the latter in turn being connected by external terminals to suitable leads of an operating-circuit which is adapted to provide an electrical potential between the iilaments by virtue of which electrons are induced to iiow from one end of the tube to the other, so as to energize the gas therein and illuminate the tube. Normally, however, the potential between the filaments is insuiiicient to initiate electron emission and hence an auxiliary starting-circuit is used to heat the respective ilaments to incandescence. The two-button snap-action, switch-unit of this inventionV is one which is adapted to close the startingand operating-circuits of the tube substantially simultaneously but to keep the starting-circuit closed only momentarily, 'the latter being opened immediately after the tube lights.

Referring to the drawings, and in particular to Fig. 1, the latter shows the improved switchunit, indicated schematically at l5, connected in the circuit of a fluorescent tube i6 which is provided at its opposite ends with nlaments I1 and i8 respectively connected across electrodes I9, 20 and 2l, 22 respectively, which in turn are provided with external terminals 23, 24 and 25, 26. The corresponding leads of the terminals 2l and 26, hereinafter identiiied by similar reference numbersLconstitute part of the starting-circuit of the switch-unit and are adapted to be connected to suitable starting-contacts, hereinafter described, of its starting-button 21. The corresponding leads of the terminals 23 and 25 are connected across the line L through operatingcontacts, hereinafter described, of the on and off or operating-button 28 of 4the switch-unit, the lead 25 having a choke-coil or ballast 29 in series to provide an induced .voltage for lighting the tube in the manner well known to the art.

The improved switch-unit l5 is shown in detail in Figs. 2 through l2 and comprises a substantially-rectangular body consisting of a coverportion Sil and base-portion 3l. In the preferred construction, both the cover and hase are molded or otherwise formedfrom plastic material having insulating properties. The cover 30 is a substantially-rectangular inverted U-shaped member comprising a top 32 and spaced-parallel side walls 33 depending substantially perpendicularly therefrom. The opposite ends of the cover are partially closed by integral depending end walls 34, the lower edges 35 of which are provided with substantially-rectangular notches 36. The latter are formed on the inside faces of the respective asesora end walls 3H and are adaptedas hereinafter described, to provide means for assembling the base 3l to the cover 30. The top 32 of the-cover is provided with two integral upstanding molded collars 3l, the inner annular walls of which are coextensive with a pair of cylindrical apertures 88 formed in the top of the cover, the centers o f the apertures 38 being on the longitudinal axis of the cover and, in the present embodiment, are spaced apart longitudinally from each other a distance substantially equal to the distance measured from the center of each respective aperture to itsrespective end of the cover. The coextensive annular walls of the apertures 38 and their respective collars 3l constitute guide-means for the upper ends of-the push buttons 27 and 28 as hereinafter described. ,A third cylindrical aperture 39 is formed on the longitudinal axis of the cover between the two guide-apertures 88 to receive an assembly-screw 48 which may be used both to mount the switch-unit on a light-harness or other supporting-means and to positively secure the cover to the base, as described below.- Referring particularly to Figs. 2 and 7, the aperture 38 is provided with a concentric collar il which is molded or otherwise formed on the underside of the top 32 of the cover and projects downwardly substantially perpendicularly thereto. Formed also on the underside of the covertop 32 and at diametrically-opposite points of the concentric collar 8i are web-members 42 which extend transversely of the cover,` each web being substantially wedge-shaped in cross section so as to provide a knife edge or fulcrum 83 for the purpose hereinafter described.

Turning again to the side walls 33 of the cover, the lower portions thereof are made somewhat thicker than the upper` portions, as indicated clearly in Figs. 4, and 6, so as to provide an outwardly-flared skirt lli at the lower edge of each side, each skirt being provided on its inside wall with a longitudinal clearance-groove L35, the upper edge of which comprises a longitudinal shoulder 356, and the lower edge of which inter.- sects the bottom edge of its respectiveside wall. Each longitudinal clearance-groove l5 is provided, moreover, with a plurality of substantiallyrectangular recesses i6 which extend longitudinally thereof and are adapted to cooperate with suitable locking-elementsv of the base, as hereinafter described, to detachably secure the base to the cover. In the present embodiment,

three locking-recesses 66 are shown, one'recess` at opposite ends respectively of each side wall and one recess intermediate the end recesses. It will be understood, however, that more than three recesses may be provided, or that a single recess extending throughout the length of the clearance-groove would be equally effective.

Referring particularly to Fig. 8, the base 3l comprises a substantially-rectangular bottom lll, the longitudinal edges of which are provided with a plurality of outwardly-projecting lugs 68 corresponding in number and location to the number andA location of the recesses 46 in the clearance-grooves of the cover. The lugs 48 constitute locking-elements for detachably securing the base to the cover and to this end are adapted to snap into the recesses 46 of the latter, as the bottom 41 of the base 3l is pushed up between the lower edges thereof. To this end, the distance'measured between the outer faces of each pair of oppositely-disposed lugs is greater than the distance between the longitudinal clearance-grooves 45 of the cover (see Fig. 5),

as a consequence of which the outwardly-projectinglugs d8 of the base-bottom 4l force the lower edges of the cover snap back and tightly grip the longitudinal sides of the bottom M of the base, the longitudinal upper edgesY thereof abutting the shoulders D of the cover and the underside of the bottom 4l, being substantially flush with the lower edges of the cover. In accordance with this construction, the base is securely but detachably fastened to the cover, thereby effecting an economy in assembly costs.

As shown in Figs, 2 and 8, each end of the base 3| is provided with an integral upstanding end wall 49 which is made substantially equal in width and height to the opening in the corresponding end of the cover so as to effectively close the latter when the base is assembled therein, as shown in Fig. 6.' Moreover, the upper edge i of each end wall 49 of the base is shown provided on its inner edge with an upstanding substantially-rectangular tongue 56 which is adapted to seat in the corresponding notch 36 in the lower edge 35 of the end wall 86 of the cover, so as to prevent the base from moving longitudinally relative thereto.

Referring more especially to Figs. 2 and 8, the

. bottom il of the base is provided intermediate its opposite ends with an upstanding substantiallycylindrical center-post 5l having a longitudinal axial aperture 52 which intersects the underside of the base-bottom il and which is provided with internal screw threads. The internally-threaded aperture 52 of the center-post 5l is adapted to be in axial alignment with the assembly-screw aperture 38 of the cover when the latter is assembled on the base, so as to receive the lower threaded end of the assembly-screw lill, whereby the cover and base may be positively held together. It will be appreciated, too, that by providing an assembly-screw of suncient length, the lower end thereof may project below the bottom of the switch so as to provide means for attaching the switch to a light-harness or other supporting-means.

Formed integrally on diametrically-opposite sides of the post are a pair of external ribs 53, each of which extends longitudinally of the post and substantially perpendicularly to the bottom'di of the base, the upper edge of each rib constituting a relatively-short transverse knife edge or fulcrum 5d. As shown in Fig. 2, each fulcrum 56 of the base is adapted to be located substantially opposite and in vertically-spaced relationship to the corresponding fulcrum 43 of the cover whenthe latter is assembled on the base.

Formed in the bottom 47 of the base between its center-post 5l and the corresponding end walls -49 are two pairs of transverse, relatively-shallow grooves 55 and 56 respectively. Each groove is substantially' U-shaped in cross section and each pair of grooves 55 and 56 respectively is separated by a transverse partition or wall 5l and 58, the

partition 58 being substantially half the height` of the partition 51, in order to provide clearance for the contact-arm of the starting-contact members which are adapted to be assembled in the grooves 56, as hereinafter described. The pair of grooves 55 differ from the pair of grooves 56 in that each groove 55 is provided at one end with a substantially-rectangular shallow reliefrecess 59 which intersects the corresponding edge of the base and is adapted to provide clearance ior the operating-contact members of the grooves 55, as set forth below. The opposite ends of the grooves 55 and the corresponding ends of the grooves 56 are provided with apertures 60 and 6| respectively which in the present embodiment are adapted to receive the leads of the terminals 24, 25 and 26 of the lamp I6 and the lead l of the lin'e L, each of these leads being arranged to be soldered or otherwise secured to the underside of one of the contact-members of the pair of contact-members 62 and 63 respectively mounted in the corresponding pairs of grooves 55 and 56 of the base. It is within the purview of the invention, however, to connect each contact-member to its respective lead by extending a terminal-portion of each contact-member through the apertures 60 and 6l of its respective groove to the underside of the base and to secure the leads to these extended terminal ends of the conductors by detachable fastening-means.

The two pairs of contact-members hereinafter referred to as the operating contact-members 62 and the starting contact-members 63 respectively, constitute elements of the switch-means and, in general, comprise relatively-thin substantiallyrectangular `sheet-metal members (see Fig. 3), each having its longitudinal edges bent downwardly and outwardly so as to make a tight nt in its respective groove of the base and to support the main body of the contact-member slightly above the bottom of the groove a distance corresponding to the depth thereof, as shown in Fig. 2. Further, each contact-member is substantially equal in length to the Width of the base so that when the cover is assembled thereon, the longitudinal shoulders 450 of its opposite lower edges will engage the opposite outer ends respectively of each contact-member to hold it iirmly in its respective groove in thevbase.

The operating-contacts 62 of the grooves 55 are preferably formed of sheet copper, although any other suitable metal maybe used, and are identical in shape, each having a terminal-arm formed integrally at the end thereof opposite that to which its respective lead is connected, the terminal-arm projecting upwardly substantially perpendicularly and having an elbow b at its upper end, as shown especially well in Fig. 6,

whereby the terminal end 66 of each arm is disf placed inwardly from the adjacent side of the cover. Moreover, the operating-contact member 62 nearest the center-post 5i is provided with an aperture 61 intermediate its opposite ends and in axial alignment with an aperture 68 in the bottoni il of the base, the aperture iid being in axial alignment with one of the cylindrical guideapertures 38 in the top of the cover, whereby the two apertures 38 and 58 constitute guide-means for the operating push button 23 of the switch, as hereinafter described. members E32 are made identical 'for effecting economies of mass production, the other contactmember B2 has a central aperture also, but this particular aperture serves no useful purpose in the assembly.

The starting-contact members 63 are preferably silver although aluminum, copper or other similar metal may be used. The outer of the two starting-contact members 63 comprises a rectangular plate with down-turned edges, as described above, whereas the starting-contact member 63 nearest the center-post 5| is provided with an integral spring-arm B9 which extends transversely thereof and is bent back upon itself, as

Since the contact-.

indicated clearly in Figs. 2 and 12, to provide a contact-arm 'l0 adapted to extend across the partition or wall 58 of the base, the outer free ture 'l2 intermediate its opposite ends and in axial alignment with a guide-aperture 'I3 in the bottom of the base, the guide-aperture 13 being in axial alignment with the corresponding guide-aperture 33 of the cover to form guide-means for the startling push button 2l of the switch-unit, as hereinafter described. A suitable slot '14 is provided in the contact-arm 'i0 of the contact-member 83 in alignment with the apertures 'l2 and 'I3 respectively to permit the push button 2l to extend therethrough, as indicated in Figs. 2 and 4.

It is customary in lighting switches of this type to provide a condenser in parallel with the lamp in order to suppress radio interference. In the present embodiment, a condenser 'l5 of substantially 0.004 microfarad capacity is adapted to be mounted on the bottom of the base adjacent one end wall 49 thereof, the longitudinal axis of the condenser extending transversely of the base. The two leads 76 and l'l of the condenser are shown soldered or otherwise secured to the respective starting-contact members 63 so as to make good electrical contact therewith.

An additional element of the switch-means is a rocker-member which, as indicated at 78, comprises a substantially-rectangular frame (see Fig. 9) made of sheet brass or other suitable metal having longitudinal sides '59 provided with downwardly-bent ilanges St, and ends Si provided with downwardly-bent flanges 82, the sides and ends of the frame defining a longitudinal substantially-rectangular aperture therein. One longitudinal side l is also provided with an integral contact-arm 33 which constitutes an extension of its respective dange tt, the contact-arm 33 being adapted to engage the terminal-arms 6d of the contacts 62, as hereinafter described. The inner edge of each side l of the rocher-member is provided with a pair of substantially-rectangular notches Btl which are spaced apart longitudinally, the notches in one side being substantially opposite the notches in the other side of the frame. lThe notches 84 of the frame are adapted to provide clearance for the lreys of the push buttons, whereby the latter may be inserted into the longitudinal aperture or" the rocker-member and lreyed therein, as hereinafter described.

The rocker-member 'i8 is adapted to be mounted in the switch-unit so as to oscillate therein and to this end the transverse distance between the inner edges oi the longitudinal sides lt of the frame corresponds to or is slightly greater than the diameter or" the center-post iii of the base, whereby the longitudinal sides 'iii oi the frame are yadapted to engage on the transverse fulcrums Eid thereof, as shown in Figs. 2 and 5. Moreover, when the cover is assembled on the base, the transverse iulcrums 43 thereof make engagement with the upper surfaces of the longitudinal sides of the frame, as a consequence of which the latter is pivotally supported for oscillating movement in the switch-unit but heid positively from either lateral or vertical displacement.

In order to provide the push buttons 2l and 28 of the switch-unit with a positive snap action,

suitable resilient-means are associated with the rocker-member to resiliently hold the latter at each extreme of its oscillating movement. Re-` ferring to Figs. 2 and 11, the resilient-means of the rocker-member comprises a pair of leafsprings 85, each of which is bowed and provided at one end with a tongue 85 and at its opposite end with a split tongue 81 having transverselyextending barbs. Each spring-member 85 is adapted to be attached to one end respectively of the rocker-member by engaging the split tongue 8l in a transverse slot 88 formed in the ange 82 at the end of the rocker-member, the barbs of the split tongue being adapted to engage on the inside of the end ange 82 to ef. fectively lock the resilient-member 85 thereto. Referring to Fig. 2, it will be noted that the spring 85 of the right-hand end of the rockermember is arranged so as to bow downwardly, whereas the spring 85 at the left-hand end of the rocker-member is arranged to bow upwardly. This particular arrangement of the respective springs is preferred since by assembling the upwardly-bowed spring at the left-hand end of the switch, enough clearance space is secured to accommodate the condenser-coil 15 which, as pointed out above, is shunted across the startingcontact members 63. The outer end of each spring 85 and more especially the tongue-portion 86 thereof, is adapted to be secured in the corresponding notch 36 of the cover-member between the upper end of the tongue 50 of the end wall 49 and the upper shoulder of the notch 36. In accordance with this construction, both springs are under maximum stress when the rockermember is in a substantially-horizontal position and, hence, each spring effectively resists displacement of the rocker-member from either extreme of its oscillatory movement, i. e the rocker-member is resiliently held at either extreme of its oscillating movement and moves from one extreme to the other with a positive snap-action. The springs 85 also serve to prevent the rockermember from moving longitudinally on its fulcrums `by engagement of the shoulders of the split tongues 8T with the respective end-flanges 82 of the rocker-member.

The rocker-member 'i8 is adapted to be operated manually by the starting and operating push buttons 2l and 28 respectively, each push button being substantially identical except that the starting-button 2 is usually red in color and the operating-button 28 black, so as to readily distinguish the functions thereof. Each button comprises a substantially-cylindrical head-portion 8S which is adapted to make a smooth sliding t in its respective collared guideaperture in the top cf the cover, the length of each cylindrical head-portion of the push but- -ton being substantially equal to one-half its overall length. The lower half of each push button comprises a shank-portion 9D immediately beneath the cylindrical head-portion, the shank 96 being substantially square in cross section and equal in width to the transverse distance between the opposite longitudinal edges of the rocker-member, whereby one pair of diametrically-opposite sides 9i of the shank-portion of each push button is adapted to make a relatively-close sliding t in the longitudinal aperture of the rocker-member. Moreover, each side 9i of the shank 90 is provided with a key or rib S2 which extends upwardly longitudinally and symmetrically of each side Si from the bottom thereof up to the shoulder 93 formed at the intersection of the upper end of the shank and the lower end of the cylindrical head-portion 89 of the button. The distance between the outer faces of the respective ribs 92 of each button exceeds the width of the longitudinal aperture in the rocker-member but is substantially equal to the distance between the oppositely-disposed notches 84 of the rocker-member. Consequently, each push button may be inserted into the longitudinal aperture of the rocker-member only by engaging its ribs 92 in the oppositely-disposed notches 84 thereof. Further, each longitudinal rib is adapted to be divided into an upper and lower rib respectively by means of a transverse slot 920, the width of the slots in the ribs of the operating-button 28 being no more than twice the thickness of a side 19 of the rocker-member, whereas the width of each slot in the ribs of the starting-button 271 is more nearly four times the thickness of a side 19 of the rocker-member. The latter construction provides for a lost-motion connection between the rocker-member and the starting-button 2l, as hereinafter described. By engaging the sides l@ of the rocker-member in the corresponding slots 920 of the push-button ribs, each push button is permitted to move longitudinally in the longitudinal aperture of the rocker-member to a position adjacent one end thereof thereby displacing the ribs 92 out of alignment with the notches 8@ in the sides 19 of the rocker-member. Consequently, the upper ends of the lower ribs are located beneath the underside of the longitudinal sides 19 of the rocker-member, whereby each push button is effectively prevented from being drawn upwardly out of the rocker-member. On the other hand, the lower end of each upper rib engages on the top of each side 'i9 of the rockermember to provide contact therewith, whereby, by pushing downwardly on the respective push buttons, the rocker-member will be oscillated on its fulcrums. Moreover, since the diametricallyopposite sides 9i of each push button makes a substantially-close fit in the longitudinal aperture of the rocker-member, the push buttons are effectively prevented from rotating therein.

Projecting downwardly from the shank-portion of each push button is a pilot 9d which comprises a cylindrical stem of relatively-small diameter adapted to make a close sliding t in the corresponding guide-apertures 6B and i3 respectively in the bottom El of the switch-unit, thereby to guide thelower ends of the respective push buttons and to prevent the push buttons from moving longitudinally in the aperture of the rocker-member.

The elements of the switch-unit are adapted to be assembled as follows: the leads 25, 1, and 2d, 2E are soldered to the corresponding pairs of contact-members 62 and 63 after which the latter are assembled in their respective grooves 55 and 56 in the base of the switch by passing the leads down through the corresponding apertures 68 and 6l therein. The condenser is then mounted at one end of the base and shunted across the starting-contacts 63. The rocker-member, including the springs secured at opposite ends thereof and the push buttons 21 and 28 engaged in its longitudinal aperture, is mounted on the fulcrums of the center-post 5l and held While the push 'buttons are moved outwardly to the outer ends of the rocker-member so as to engage the pilotstems 93 at the lower ends of the push buttons in the guide-apertures in the base of the switch. The tongues at the outer ends of the springs 85 are then engaged on the upper edges of the lugs 5U of the end walls', whereupon the cover is slipped the springs aresimultaneously pinched between the upper edges of the respective lugs l! and the shoulders of the recesses of the cover, while the fulcrums of the latter engage on the upper surfaces of the oscillatable rocker-member to hold it down firmly on the fulcrums of the centerpost. Although the coactlon of the lugs of the base and the recesses in the cover serves admirably to detachably secure the cover to the base, it is desirable to positively hold the two elements together by the assembly screw 40 which is inserted into the hole in the cover and threadedly engaged at its lower end in the internallythreaded aperture of the center-post.

The operation of the switch-unit maybe described brieily as follows. Assuming the leads of the starting push button 2'! nd the leads of the operating push button 28 are connected in the lamp circuit, as indicated in Fig. 1, then when the operating-button 28 is in its lowermost position, as indicated in Fig. 2, the lamp will be oif since the rocker-member has been oscillated clockwise thereby moving'its contact-arm 83 below the vterminal-arms of the operating-contact members 52, as indicated in Fig. 6. To light the lamp, the operator pushes the starting-button 21 downwardly to oscillate the rocker-member in a counterclockvvise direction, indicated by the broken lines in Fig. 2, thereby elevating the contact-arm E33 of therocker-member into engagement with the upper ends 66 of the terminalarms of the operating-contacts 62. Simultaneously, as the starting-button 21' is pushed down, the iower end of its substantially-rectangular shank is adapted to engage the contact-arm ld oi the starting-contacts 63 at the left-hand end of the switch-unit, so as to depress the outer free end 'it of the contact-arm into engagement with the outer starting-contact members 83 thus closing the' circuit between the two starting-contact members 63. Consequently, the circuit is completed from the laments il and iii at opposite ends of the lamp i6 to the line L,

whereupon the laments are heated to incandescence so as to effect an emission oi electrons and energize the gas in the lamp to illuminate the latter. As soon as the tube 'E illuminated, the operator releases the starting-button 2li and the resiliency oi the contact-arm lifts up the startingbuiton slightly, which action is permitted by the lost-motion connection between the startingbutton 21 and rocker-member, as hereinabove described, and breaks the connection between the two starting-contacts 53 soV as to cut oif the flow oi current to the iilaments of the tube. The contact-arm of the rocker-member remains, how-s1 ever, in engagement within the upper ends @t of the terminal-arms of the operating-contact members Eii and, hence, the line potential is maintained between the filaments of the lampto continue the iioiv of electrons between opposite ends thereof. Since the time required to heat the filaments to incandescence' is ordinarily a matter of but a iractionpof a second, the operator holds down the starting-button 21 only long enough to momentarily close the starting-contacts 63. in order to put the light out, the operator simply presses down the operating-button 28 so as to oscillate the rocker-member clockwise and disengage its contact-arm from th terminal-arms of the operating-contact members 62, thereby opening the circuit to the filaments of the lamp.

The invention may be carried out in other specific ways than those herein set forth without departing from the spirit and essential characteristics of the invention, and the present embodilments are, therefore, to be considered in all respects as illustrative and not restrictive, and al1 changes comi-ng within the meaning and equivalency range of the appended claims are intended to be embraced therein.

We claim:

l. A switch-unit comprising a body of insulating material; switch-means mounted in said body of insulating material comprising a pair of contacts adjacent opposite ends respectively of said body and a rocker-member supported intermediate its opposite ends in said body so as to oscillate into and out of engagement with one pair of contacts; and separate manually-operated members mounted in said body and arranged to engage said rocker-member at opposite ends thereof respectively so as to oscillate said rockermember thereby to alternately close and open said one pair of contacts, one of said separate members having a lost-motion connection with said rocker-member and arranged both to actuate said member to close said one pair of contacts and simultaneously to close the second pair of contactsv and by its lost-motion connection with said member to open said second pair of contacts without opening the said one pair of contact-s.

2. A switch-unit comprising a body of insulating material; switch-means mounted in said body of insulating material comprising a pair of contacts at one end of said body and a second pair of contacts including a resilient contact-arm at the opposite end of said body, a iuicrum in said body, and a rocker-member mounted on said fulcrum intermediate its opposite ends so as to osciilate into and out of engagement with one pak of contacts at opposite extremes respectively of its movement; and. separate manually-operated members mounted in said body and arranged to engage said rocker-member at opposite ends thereof respectively to oscillate said rocker-member thereby to alternately close and open said one pair ci contacts, one of said separate members being arranged also to engage the resilient contact-arm of said second pair or contacts to close the second pair of contacts substantially simultaneously with the closing ci said one pair of contacts, said resilient contact-arm being arranged to automatically open said second pair of A contacts on release or" said one separate member. 3. A switch-unit comprising a body of insulating material; switch-means mounted said body oi insulating material comprising a pair of contacts adjacent opposite ends respectiveiy oi' said body, a fuis-rum in said body, a rocker-member mounted on said iulcrum intermediate its opposite ends so as to oscillate into and out of engagement with one pair oi contacts at opposite extremes respectively oi its movement, and an overcenter spring secured at each end of said rockermember substantially in alignment with the longitudinal axis thereof to resiliently hold said rocker-member at the opposite extremes of its movement; and separate manually-operated members mounted in said body and arranged to engage said rocker-member at opposite ends 'thereof respectively to oscillate said rocker-member thereby to alternately close and open said one A l l1 pair of contacts, one ofrsaid separate members being arrangedalso to momentarily close the second pair of contacts;

4. A switch-unit comprising a body of insulating material; switch-means mounted in said body of insulating material comprising a pair of contacts adjacent opposite ends respectively of said body and a longitudinally-slotted rocker-member supported intermediate its opposite ends in said body so as to oscillate in'to and out of engagement with one pair of contacts at opposite extremes respectively of its movement; and a pair of push buttons mounted in said body, each push button being constructed and arranged to make nonrotatable engagement in the longitudinal slot of said rocker member adjacent opposite ends thereof respectively, and each push button having a transverse shoulder arranged to engage on said rocker-member so as to oscillate said rocker-member thereby to alternately close and open said one pair of contacts, one of said push buttons being arranged also to momentarily close the second pair of contacts.

5. A switch-unit comprising a body of insulating material; switch-means mounted in said body of insulating material comprising a pair of contacts adjacent opposite ends respectively of said body and a longitudinally-slotted rocker-member supported intermediate its opposite ends in said body so as to oscillate into and out of engagement with one pair of contacts at opposite extremities respectively of its movement; and a pair of push buttons mounted in said body, each push button comprising a substantially-rectangular shankportion arranged to make nonrotatable engagement in the longitudinal slot of said rockermember, an enlarged head at the upper end of said shank and a depending pilot at the lower end of said shank, said head and pilot of each respective push button being arranged to slide in axially-aligned apertures in the top and bottom respectively of said body to guide the push button, said enlarged head-portion of each push -button being adapted to form a transverse shoulder arranged to engage on said rocker-member adjacent opposite ends thereof respectively so as to oscillate said rocker-member thereby to alternately close and open one pair of contacts, one of said push buttons being arranged alsofto momentarily close the second pair of contacts.

6. A switch-unit comprising a body of insulating material; switch-means mounted in said body of insulating material vcomprising a pair of contacts adjacent opposite ends respectively of said Ibody and a longitudinally-slotted rocker-member lsupported intermediate its opposite ends in said body so as to oscillate into and out of engagement with one pair of contacts at opposite extremes respectively of its movement; and a pair of push buttons mounted in saidbody, each push button comprising a shank-portion having at least two diametrically-opposite at sides arranged to engage in the longitudinal slot of said rockermember to prevent rotation of said push buttons therein, and each push button having a transverse shoulder above said shank-portions arranged to engage on said rocker-member adjacent opposite ends thereof respectively so as to oscillate said rocker-member thereby to alternately close and open said one pair of contacts, one of said push buttons being arranged also to momentarily close the second pair of contacts.

7. A switch-unit comprising a body of insulatof insulating material comprising a pair of contacts adjacent opposite ends respectively of said body and a longitudinally-slotted rocker-member supported intermediate its opposite ends in said body so as to oscillate into and out of engagement with one pair of contacts at opposite extremities respectively of its movement; and a pair of push buttons mounted in said body, each push button comprising a shank-portion having at least two diametrically-opposite at sides arranged to engage in the Vlongitudinal slot of said rockermember to prevent rotation of said push buttons therein, laterally-projecting ears. on the shank of each push button, said ears being arranged to engage the underside of the longitudinal edges of the slot in said rocker-member to prevent said push button from moving upwardly therein, and shoulders projecting transversely from the shankportion of each push button. and arranged to engage on the topside of the longitudinal edges of said slot to prevent said push buttons from moving downwardly therein, said push buttons being arranged to engageopposite ends of said rocker-member so as to oscillate said rockermember thereby to alternately close and open said one pair of contacts, one of said push buttons being arranged also to momentarily close the second pair of contacts.

8. A switch-body comprising a body-portion having a base-portion and a separate cover-portion, each consisting of an insulating material; a protuberanceprojecting -upwardly from said base-portion intermediate .the opposite ends thereof and provided with laterally-projecting knife-edges; a protuberance projecting downwardly from said cover-portion intermediate the opposite ends thereof and provided with laterallyprojecting. knife-edges, said cover-portion being arranged to be detachably assembled on said baseportion whereby the respective knife-edges of said cover and said base constitute upper andl lower fulcrums '1n vertically-spaced relationship; switching-means mounted in said base-portion comprising a pair of contacts adjacent opposite ends respectively of said base and a rockermember comprising a longitudinally-slotted substantially-rectangular plate, said rocker-member being arranged to be .oscillatingly supported intermediate its opposite ends between said upper and lower fulcrums and adapted at one extreme of its oscillating movement to close one pair of contacts; and a pair of push buttons mounted in said cover-portion, said push buttons being arranged to engage in the slot of said rocker-member adjacent opposite ends thereof to Yoscillate said member thereby to alternately close and open said one pair of contacts, one of said push buttons being arranged also to momentarily close the second pair of contacts.v

9. A switch-body comprising a body-portion having a base-portion and a separate cover-portion, each consisting of an insulating material; a post projecting upwardly from said base-portion intermediate the opposite ends thereof and provided with laterally-projecting knife-edges; a collar projecting downwardly from saidocoverportion intermediate the opposite ends thereof and provided with laterally-projecting knifeedges, said cover-portion being arranged to be detachably assembled on said base-portion whereby the respective knife-edges of said cover and said base constitute upper and lower fulcrums in vertically-spaced relationship; switching-means mounted in said base-portion comprising a pair ing material; switch-means mounted in said body of vcontacts adjacent opposite ends respectively of said base and a rocker-member comprising av longitudinally-slotted substantially-rectangular plate, said rocker-member being arranged to be oscillatingly supported intermediate its opposite ends between said upper and lower fulcrums and adapted at one extreme of its oscillating movement to close one pair of contacts; a pair of push buttons mounted in said cover-portion, said push buttons being arranged to engage in the slot of said rocker-member adjacent opposite ends thereof to oscillate said member thereby to alternately close and open said one pair of contacts, one of said push buttons being arranged also to momentarily close the second pair of contacts; and resilient means supported at opposite ends of said cover and arranged to engage corresponding ends of said rocker-member to resiliently hold said rocker-member at opposite extremities of its oscillating motion.

10. A switch-body comprising a body-portion having a base-portion and a separate cover-portion, each consisting of an insulating material; a post projecting upwardly from said base-portion intermediate the opposite ends thereof and provided with laterally-projecting knife-edges; a collar projecting downwardly from said coverportion intermediate the opposite ends thereof and provided with laterally-projecting knifeedges, said cover-portion being arranged to be detachabLv assembled on said base-portion whereby the respective knife-edges of said cover and said base constitute upper and lower fulcrums in vertically-spaced relationship; switching-means mounted in said body comprising a pair of contacts mounted in said base at opposite ends thereof respectively, and a rocker-member comprising a longitudinally-slotted substantially-rectangular plate, said rocker-member being arranged to be oscillatingly supported intermediate its opposite vends between said upper and lower fulcrums and adaptedat one extreme of its oscillating movenient-to close one pair of contacts; a pair of push buttons mounted in said cover-"portion, said push buttons being arranged to engage in the slot of said-rocker-member adjacent opposite ends thereof tol oscillate said member thereby to alternately close and open said one pair of contacts,

.one of said push buttons being arranged to momentarily close the second pair or contacts. Iresilient-means mounted in said cover at opposite ends thereof, said resilient-means being arranged to'engage corresponding ends of said rocker- 4 to the longitudinal axis of said body, said condenser being connected to the adjacent pair of contacts.

11. A switch-body comprising a body-portion having a base and a separate cover, each consisting of an insulating material; a protuberance projecting upwardly from said base intermediate the opposite ends thereof and provided with laterallyprojecting knife-edges; a protuberance projecting downwardly from said cover intermediate the opposite ends thereof and provided with laterallyprojecting knife-edges, said cover being arranged to be detachably assembled on said base whereby the respective knife edges of said cover and said base constitute upper and lower fulcrums in vertically-spaced relationship; switching-means mounted in said base-portion comprising a pair of contacts adjacent oppositeends respectively of said base, one pair of contacts having a resilient contact-closing arm arranged normally in spaced relationship to its respective contacts, and a rocker-member comprising a longitudinally-slotted substantially-rectangular plate having a contact-closing arm at one end, said rocker-member being arranged to be oscillatingly supported intermediate its opposite ends between said upper and lower fulcrums and adapted at one extreme -of its oscillating movement to engage its contactclosing arm with the said second pair of contacts a pairof push buttons mounted in said cover, said push buttons having substantially-rectangular shank-portions arranged to engage in the slot of said rocker-member to prevent rotation of said push buttons therein; push-button guide-means in said cover and said base; and a transverse shoulder on each push button arranged to engage on said rocker-member adjacent opposite ends thereof to oscillate said member thereby to alternately close and open said second pair of contacts, one of said push buttons being arranged to engage the contact-closing arm of the said first pair of contacts to momentarily close the latter as the contact arm of said rocker-member is moved into contact with said second pair of contacts.

GEORGEv B. HORN. HOWARD E. YOUNGS.

REFERENCES CITED The following references are of record in the ille of this patent:

UNITED STATES PATEN'IS Number Name Date 1,047,245 Knaun Dec. 17, 1912 1,287,425 Platt Dec. 10, 1918 1,399.129 Laub Dec. 6, 1921 1,518,041 Avery Dec. 2, 1924 2,041,685 Barkelew May 26, 1936 2,228 523 Johnson Jan. 14, 1941 2,299,250 Perbal Oct. 20, 1942 2,416,569 Cianchi Feb. 25, 1947 

